Abbotsford firefighters had to truck in water from the city's airport to fight a wood-chip fire Thursday night. (CBC)

Southwestern B.C.'s long spell of dry weather is having serious effects on water supplies from the Sunshine Coast, to the Gulf Islands and beyond.

On the Sunshine Coast, northwest of Vancouver, a lake that supplies much of the summer water supply is 80 per cent empty.

Restrictions have been ramped up to "stage four," meaning residents are not allowed to water their gardens, lawns or even wash their vehicles, said manager Dave Crosby.

"I've been in this organization for 33 years and we have never gone to stage three or four," Crosby said.

On the Gulf Islands, some wells have already run dry, while other are being monitored closely for contaminants.

Low water levels could allow seawater or even arsenic to enter wells, according to Mary Cooper, of the Mayne Island Integrated Water Systems Society.

Cooper said it will take years before the aquifer, where wells draw their water, has recovered.

"It's going to take two year to get that water down to the aquifer," Cooper said. "In about two years from now, you're going to see a lot of dead trees. That's the first thing that gets hit is the flora, so now we're looking at a fire hazard."

Vancouver Island restrictions soon

The next two weeks will be crucial for water supplies in almost all Vancouver Island communities and if the dry spell continues, they too could impose watering restrictions.

Things aren’t much better on the mainland.

In Abbotsford Thursday night, crews battled a wood chip fire with flames almost 20 metres high and firefighters had to truck in water from the airport to keep the fire under control.

"This is about the driest I’ve seen at this time of the year and the fire risk is extremely high, even though we're getting colder nights," said assistant Abbotsford fire chief Dave Rivett.